Cleanup: Remove Dispatcher and UserScript classes from builds where extensions are disabled.

chrome/renderer/extensions/extension_frame_helper.cc

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/renderer/extensions/extension_frame_helper.h"
 
 #include "content/public/renderer/render_frame.h"
 #include "extensions/common/extension_messages.h"
 #include "extensions/renderer/console.h"
 #include "extensions/renderer/dispatcher.h"
 #include "third_party/WebKit/public/web/WebConsoleMessage.h"
 #include "third_party/WebKit/public/web/WebLocalFrame.h"
 
 namespace extensions {
 
 ExtensionFrameHelper::ExtensionFrameHelper(content::RenderFrame* render_frame,
                                            Dispatcher* extension_dispatcher)
     : content::RenderFrameObserver(render_frame),
       content::RenderFrameObserverTracker<ExtensionFrameHelper>(render_frame),
       extension_dispatcher_(extension_dispatcher) {}
 
 ExtensionFrameHelper::~ExtensionFrameHelper() {
 }
 
 void ExtensionFrameHelper::WillReleaseScriptContext(
     v8::Handle<v8::Context> context,
     int world_id) {
+// TODO(thestig): Remove scaffolding once this file no longer builds with
+// extensions disabled.
+#if defined(ENABLE_EXTENSIONS)
   extension_dispatcher_->WillReleaseScriptContext(
       render_frame()->GetWebFrame(), context, world_id);
+#endif
 }
 
 bool ExtensionFrameHelper::OnMessageReceived(const IPC::Message& message) {
   bool handled = true;
   IPC_BEGIN_MESSAGE_MAP(ExtensionFrameHelper, message)
     IPC_MESSAGE_HANDLER(ExtensionMsg_AddMessageToConsole,
                         OnAddMessageToConsole)
     IPC_MESSAGE_UNHANDLED(handled = false)
   IPC_END_MESSAGE_MAP()
   return handled;
 }
 
 void ExtensionFrameHelper::OnAddMessageToConsole(
     content::ConsoleMessageLevel level,
     const std::string& message) {
   console::AddMessage(render_frame()->GetRenderView(), level, message);
 }
 
 }  // namespace extensions